1. Field of the Invention
The present invention relates to a water treatment process and an apparatus thereof and more particularly, to a multistage process and a package apparatus thereof for removal of dissolved, colloidal, suspended, volatile, and living contaminants from water or wastewater.
2. Description of the Prior Art
Various types of water treatment processes are well known in the art. In such processes, the suspended contaminants in water are commonly removed by a sedimentation separation procedure wherein the particles in suspension have a specific gravity greater than that of the water in which they are suspended. When the specific gravity of the suspended contaminants is similar to that of the water, then a dissolved air flotation separation procedure is more effective and is employed Several types of prior art processes have been developed for the separation of suspended particulates from a water.
It has been a standard practice for engineers to construct separate water treatment units to remove dissolved, colloidal, suspended, volatile and living contaminants, and to construct separate aeration units for oxidation, air dissolving, distribution, corrosion control, biological fouling control, and scale control For example, for soluble iron and manganese removal in a conventional water treatment system, an aerator or an oxidizer is required to convert a soluble contaminant to its insoluble form by oxidation. Conventionally, chlorination is used for biological fouling control. Hardness reduction or softening is essential for scale control, and pH adjustment and anti-corrosion agent are needed for corrosion control.
Both such conventional sedimentation systems and conventional flotation systems involve the use of separate mixers, monitors, flocculators, chlorinators, softeners, clarifiers, and anticorrosion chemical feeders.
Particularly, such conventional flotation systems require separate pressure vessels for dissolving gas and for gas bubble generation. Therefore, the capital costs and land space requirements of such conventional flotation and sedimentation systems are high.
Such conventional water and wastewater treatment processes and apparatuses therefor are described in the U.S. Pat. No. 3,171,804 to Rice, U.S. Pat. No. 3,307,701 to Krofta, U.S. Pat. No. 3,820,659 to Parlette, U.S. Pat. No. 4,022,696 to Krofta, U.S. Pat. No. 4,151,093 to Krofta, U.S. Pat. No. 4,157,952 to Krofta, U.S. Pat. No. 4,184,967 to Krofta, U.S. Pat. No. 4,303,517 to Love et al, U.S. Pat. No. 4,377,485 to Krofta, U.S. Pat. No. 4,626,345 to Krofta, U.S. Pat. No. 4,626,346 to Hall, U.S. Pat. No. 4,673,494 to Krofta, U.S. Pat. No. 4,673,498 to Swinney et al, U.S. Pat. No. 4,673,500 to Hoofnagle et al and L. K. Wang, Using Air Flotation and Filtration in Color and Giardia removal. U.S. Department of Commerce, National Technical Information Service, Springfield, Virginia, USA. Technical Report No. PB89-158398/AS October 1988 L. K. Wang and W. J. Mohoney. Treatment of Storm Run-off by Oil-Water Separation, Flotation, Filtration and Adsorption, Part A: Wastewater Treatment. Proceedings of the 44th Industrial Waste Conference, P. 655-666, May 1989. L. K. Wang, M. H. S. Wang and W. J. Mahoney. Treatment of Storm Run-off by Oil-Water Separation, Flotation, Filtration and Adsorption: Part B: Waste Sludge Management. Proceedings of the 44th Industrial Waste Conference, P. 667-673, May 1989. L. K. Wang, M. H. S. Wang, Bubble Dynamics and Air Dispersion Mechanisms of Air Flotation Process Systems, Part A: Material Balances Proceedings of the 44th Industrial Waste Conference, P. 493-504, May 1989.